AMSTERDAM—Achilles Netherlands Holdings B.V. last week cleared important hurdles in its proposed acquisition of Lloyd’s of

London firm Brit Insurance Holdings N.V. and reduced the required acceptance rate to 80% for the deal to proceed.

One day after the deal received approval from the Financial Services Authority, the U.K.’s insurance regulator, and Lloyd’s,

Achilles reduced its required acceptance rate to 80% from the previous 95%.

At that point, Achilles said it had already received approval from more than 75% of Brit’s shareholders. Achilles also extended the deadline to approve the takeover to March 5.

Sources had said that they expected the FSA and Lloyd’s approvals to prompt more U.K shareholders to accept the £888 million ($1.38 billion) buyout.

In addition, an announcement expected this week of the size of a contingent value payment that makes up part of the deal also may spur remaining Brit shareholders to accept Achilles’ offer, sources said.

Under the terms announced earlier, Brit shareholders would receive £10.25 ($16.40) per share in cash plus a contingent value

payment of up to 25 pence (40 cents) per share.

Achilles, an Amsterdam-based holding company formed on behalf of funds managed by Apollo Management VII L.P. and funds advised by CVC Capital Partners Ltd., last October reached an agreement with Brit’s board over terms that ended its long-running bid for the company.

Achilles first approached Brit last June, but Brit rejected its first two offers.

Brit, which is based in Amsterdam, underwrites multiline insurance and reinsurance through a Lloyd’s syndicate and a U.K. insurance company.

Achilles recently announced that, if the takeover goes ahead, it plans to appoint a former Lloyd’s executive to head Brit. Nick Prettejohn was CEO of Lloyd’s for six years. He then served as CEO of Prudential P.L.C. in the United Kingdom and Europe, and most recently has been a nonexecutive director at London-based Legal & General Group P.L.C.

Mr. Prettejohn would succeed John Barton, whose term as Brit’s chairman would end when the deal has been completed.

Brit is not the only Lloyd’s company to be a takeover target. Also this month, Chaucer Holdings P.L.C. said it had received several approaches.

Private equity company Terra Firma Capital Partners III L.L.P. said it is considering making an offer for Chaucer, which underwrites multiline insurance and reinsurance and operates two syndicates at Lloyd’s.

In 2009, Brit withdrew a bid for Chaucer after Chaucer declined to recommend the deal to its shareholders.

And in January, Guernsey-based Canopius Group Ltd. made an unsolicited offer for Bermudabased Omega Insurance Holdings

Ltd.

Omega, which operates syndicate 958 at Lloyd’s, said there was no guarantee of a formal offer being made, but it also said it

would consider any approach that it deemed to be of benefit to its shareholders.

Canopius manages syndicates 4444, 260 and 839 at Lloyd’s, and has a specialty lines company that underwrites on behalf of syndicate 4444.